Trouble for activists could start right at Hong Kong airport, where authorities have rolled out a red carpet for ministerial delegates and high officials.

Among those taken aside for interrogation were French farmer and activist Jose Bove, three Thai campaigners and four prominent Filipinos - - including leaders of the country's left-wing political movement, its largest feminist organisation and a prominent trade union leader.

"They started to ransack and go through my luggage," says Elisa Dita Lupi of the Filipino Gabriella women's party. "They started separating and listing down anti-WTO materials like leaflets and streamers and stickers and for a while I thought they were going to confiscate them, but eventually they relented and I got to gather my things."

Norma Binas, a leader of the Philippines May 1st Movement Labour Center, said she was flagged for interrogation at passport control and then escorted by 10 police officers with machine-guns to a special solitary interrogation room.

According to Binas, the interrogators almost immediately turned their attention to her group's political activities. "I told them that I have come for the workers workshops," she said. "So the police asked me if I had an invitation and I told them that it's on the internet. Everyone is invited maybe you can look for it."

Binas said she was interrogated for six hours: "They had a two-page questionnaire, asking whether we are involved in anti-globalisation activities in our own country. So I told them the situation of the workers in the Philippines -- protesting is the least they can do when they're losing their livelihoods."

Eventually, all the activists detained at the airport were released, though the Associated Press reports that French Trade Minister Christine Lagar had to intervene to get Bove out of the airport.

Once activists arrive in the city, they are met by a gauntlet of security measures. A force of 9,000 police has been deployed on round- the-clock foot patrol around the convention centre where the week-long WTO ministerial will be held.

In recent days, police have rigged wire mesh across pedestrian walkways, sewer gates have been welded shut, truckloads of barricades have been put up, and miles of 10-foot high linked water-filled crowd control barriers have been erected along the perimetre of an exclusion zone around the convention centre.

There have also been raids at places where the activists are camping.

The Indonesian Migrant Workers' Association, which helped organise a peaceful demonstration of thousands of domestic workers against the WTO on Dec 11, is being visited several times each day by Hong Kong police.

"They say they're looking for illegals, but this is never something that concerned them before," says one organiser who refused to give her name for fear of deportation. "Everybody is worried right now. They're afraid. What we're doing is not wrong, so why are the police doing things like that?"

The organiser says a van with five officers has been stationed nearly permanently outside their office door.

"This is not reasonable," she said. "They say they just wanted to check. But everything is peaceful so how come they came so many times. It has been four or five times in a day. They don't have any reason."

Police fear that during the Dec. 13-18 ministerial, violence of the type that marked earlier WTO meets in Seattle and Cancun, Mexico could erupt and seem to be taking no chances.

Anti-WTO activists have planned a second major demonstration as the WTO meetings begin Tuesday afternoon. The first of three scheduled major rallies was on Sunday. Hong Kong Police have stepped up security measures across the territory.

In comments over the weekend, Hong Kong Chief Executive Donald Tsang Yam-kuen downplayed any allegations of police harassment.

"This is the first time ever in any WTO meeting that we actually have NGOs inside the conference facilities side-by-side with the delegates," he told the South China Morning Post.

The NGOs he was speaking of are the relatively small group of more established think tanks allowed inside the convention centre. "This is a demonstration not only of the host but also the WTO (itself) attitude towards the exchange of views," the chief executive added.

Still, the security steps have been stringent enough to catch the eye of the human rights group Amnesty International.

In an open letter to Hong Kong security chief Ambrose Lee Siu-kwong, Amnesty's Hong Kong chairwoman Si-si Liu Pui-san expressed concern that the police do not treat the protests with "sensitivity and in line with international human rights standards of freedom of expression, association, and assembly".